Manufacture of stay-bolts.



JOHN ROG-ERS FLANNERY, OF PITTSBURGH, PENSYLVANIA, SSIGN'ORTO `FLAIU'QN'EEIRY BOLT COMPANY, OF PITTSBURGH, lE1\T1\l'SYLVANIA.`

MANFACTURE or STAY-noms.

To all 'whom t may concern:

Be it known that I, JOHN R. FLANNERY, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in the Manufacture of Stay-Bolts; and I do hereby declare the following to be a full, clear, and exact description `of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements 1n the manufacture of staybolts for boilers,- one object of the invention being to produce a stay bolt for boilers which shall have a tell-tale hole adapted to discharge at the inner end of the bolt and extending through the length of the bolt with its portion at the headed end of the bolt closed, whereby the manufacture of the bolt shall be facilitated and its cost of production shall be reduced to a minimum without sacrificing efliciency, and whereby breakage of the bolt at any point between the boiler plates will permit the entrance of steam or water which may find exit through the inner end of the bolt.

With this and other objects in view, the invention consists in certain features as hereinafter set forth and pointed out in the claims.

In the accompanying drawings; Figure l is a view illustrating the first and second steps of the method; Fig. 2 is a view illustrating the third step; F ig'. 3 is a view illustrating the fourth step; Fig. 4 is a view of a stay bolt structure showing the completed staybolt, and Fig. 5 is a view showing a modification.

1 represents an outer boiler sheet and 2 the inner sheet. In the construction shown in the drawing, the outer boiler sheet is made with. an opening having a threaded wall for the accommodation of a sleeve 3 in which the spherical head 4 of the stay bolt 5 has its bearing, said sleeve extending outwardly from the boiler sheet l to receive the cap 6, and-the inner sheet 2 is made with a hole having a threaded wall for the accommodation of the threaded inner end of the stay bola-all of which as thus far described being well. known in.. the art.

Specification of Letters Patent. `153|;3e111`5d June 1918 Application led March 7, 1917. Serial No. 153,066.

In constructing the staybolt, I rst bore a hole which forms a tell-tale hole 7, through a bar of iron from one end to the other thereof, I then close one end portion of the bore by inserting thereinto, a temporary plug 8 of such material as will permit the same to be subsequently removed. Thus this plug may be made of material which may be fused out of the bore. W'hile the fusible plug is in the end portion of the bore, the head t is forged on the outer end of the bolt (Fig. 2). The temporary plug will be removed leaving the bore continuous from end to end (Fig. 3), and I then insert a plug 9, preferably of' suitable metal, into the bore at the headed end of the bolt, and said plug may be spot-welded in place in said bore or screwed in as shown in Fig. 5 and the head 4 will be slotted as at 10 to receive a screw-driver. When the bolt is placed in position as shown in the drawing, its inner end will be upset against the inner boiler sheet 2 as indicated at l1.-

It will be observed that when the manufacture of the bolt has been completed, the tell-tale hole will extend longitudinally through the bolt, with its inner end open and its outerend (within the head of the bolt) closed by the plug 9, so that a rupture in the bolt at any place between the boiler sheets will permit the entrance of water or steam or both, which may be discharged from the inner open end of said tell-tale hole and thus indicate the 'defective condition of the bolt.

Having fully described my invention what I claim as new and desire tosecure by Letters-Patent, is:

l. The method of making a staybolt, consisting in forming a hole longitudinally through a bar of iron, temporarily closing one end portion of the hole, forming a head on this end of the bar, removing the temporary closure, and permanently .plugging the end of the hole within the headed end of the bar.

2. A method of making a staybolt, consisting in forming a hole longitudinally through a bar of iron, securing a fusible plug in said hole to close the end thereof on which the head of the bolt is subsequently formed, forging a head on the end of the bolt Within which the fusible plug is located, removing the fusible plug, thus leaving :L continuous bore, and permanently closing the forged end leaving the bore oon- 5 tnuous from the inner end of the bolt to at point Within the headed end.

In testimony whereof, I have signed this copies o! this patent may be obtained for JOHN ROGERS FLANNERY.

Witnesses:

F. I-I. ALLIsoN, ETHAN I. DoDDs.

ve centsA each, by addressing the Commissioner o f Patents. Washington, 11.0. 

